Welcome to the NPDES Water Quality information page. The information below provides a summary of the various water quality requirements that must be met throughout the project development and construction process. You will be provided a single point of contact during each of these phases. Should you have any questions, please contact our Customer Service line (714) 667-8888.
The County’s NPDES Program enforces State mandated water quality regulations that apply to construction projects in the unincorporated area. These regulations are intended to minimize pollutants and runoff from both construction sites and completed project sites. The County has established requirements that owners, developers, contractors and builders must meet at each stage of the project development process in order to achieve compliance. These NPDES requirements have been integrated into the project application/permit approval process and construction site inspection system. These requirements include the following (A flow chart summary can be found here).
- Non-exempt Priority Development projects must prepare and submit a project specific Water Quality Management Plan (WQMP) prior to the issuance of any grading or building permit. The WQMP describes the permanent, post-construction Best Management Practices (BMPs) that will be constructed or utilized on the site and maintained during the life of the project.
- An Erosion and Sediment Control Plan (ESCP) must be submitted with each set of grading and building plans submitted for Plan Check. The ESCP describes the appropriate BMPs that will be used throughout the construction (grading and building) phase.
- NPDES inspections will be conducted on all construction sites to ensure that appropriate BMPs are kept in place throughout the construction phase. The frequency of these inspections is regulated by a State mandated schedule for both wet and dry seasons.
- After construction has been completed, property owners are responsible for the ongoing operation and maintenance of all structural and non-structural water quality BMPs on their property and may be required to obtain a 12-month post-construction inspection of treatment control BMPs.
To get started, first, determine which regional jurisdiction your property/project is located. Click here to use this link and your address to find out!
Second, determine if your project is a priority, non-priority, or exempt project. Click here and fill out the Priority Development Checklist to determine your project category.
Based on your project determination the following requirements may apply.
PRIORITY DEVELOPMENT PROJECT BMP IMPLEMENTATION AND OVERSIGHT
Each project proponent must implement a program that requires and confirms structural BMPs on all Priority Development Projects are designed, constructed, and maintained to remove pollutants in storm water to meet the criteria set forth in Model WQMP, TGD, and HMP. Documents based on your regional jurisdiction can be found at the following link:
County of Orange BMP Design Manual
NON-PRIORITY DEVELOPMENT PROJECT BMP IMPLEMENTATION AND OVERSIGHT
Non-Priority Projects are projects that do not meet any of the categories to be called a Priority Project have a non-negligible potential for stormwater pollution. Reference the Priority Development Checklist found above. If your project is considered a Non-Priority Project, follow the guidance documents for your jurisdictional region at the link below.
County of Orange BMP Design Manual
EXEMPT PROJECTS
Exempt projects do not fall into either Priority or Non-Priority development categories and are therefore exempt. These projects still need to follow construction best management practices which can be found below.
CONSTRUCTION WATER QUALITY (NPDES) INFORMATION AND ADDITIONAL RESOURCES
